Nitrated Fatty Acids, Novel Anti-inflammatory Mediator in Allergic Airway Disease

摘要 哮喘是一种高度流行的气道疾病，是一个主要的公共卫生问题， 选择是不够的。内源性硝化脂肪酸（NFA），被认为是由NO产生的， 最近被鉴定为存在于人血浆中的重要生物活性化合物。虽然调查 它们的生物学活性尚处于早期阶段，证据正在积累，表明它们具有强效抗炎作用 分子。我们的初步数据表明，外源性NFA的管理可以显着减弱 在过敏性气道疾病的小鼠模型中的病理生理表现，而抑制内源性 NFA合成加剧过敏反应。NFA激活核转录因子过氧化物酶体 增殖物激活受体-<$（PPAR-<$）在某些细胞类型，我们已经发现，过敏反应是 当PPAR-<$被基因消除时会加重，但气道中的PPAR-<$过表达会减弱 体内上皮细胞。因此，我们建议验证气道上皮细胞活化的假设， 硝酸化脂肪酸产生的过氧化物酶体增殖物激活物激活物受体（PPAR-1）可显著抑制过敏性气道疾病的影响，包括 炎症和粘液产生。我们的具体目标是：1）确定NFAs调节 肺中的过氧化物酶体增殖物激活物受体活性和小鼠过敏性气道疾病的严重程度，我们将使用小鼠 组成性缺乏一氧化氮合酶的所有三种亚型（三重NOS敲除），因此预期 缺乏NFAs; 2）确定气道上皮细胞中的PPAR-β活化是否介导NFAs抑制 过敏原激发在小鼠过敏性气道疾病中的作用，我们将使用具有PPAR-的小鼠， 在气道上皮细胞中选择性地敲除或过表达;和3）确定NFA是否抑制 在培养的人气道上皮细胞中趋化因子和粘液的产生以及这些趋化因子和粘液在多大程度上 效应是通过PPAR依赖性和/或PPAR非依赖性机制介导的，为此，我们将 使用基因沉默和化学抑制来抑制PPAR-γ，同时检测其他信号的激活 途径。对于目的1和2，我们将利用已建立的过敏性气道疾病的小鼠模型， 蟑螂变应原，而Aim 3将在体外使用分化良好的原代人支气管 在气液界面生长的上皮细胞。验证我们的假设将确定和阐明 一种新的内源性物质调节过敏性气道疾病严重程度的机制 并可能导致哮喘的新的治疗途径和治疗。

ABSTRACT Asthma is a highly prevalent airway disease that is a major public health problem for which available treatment options are inadequate. Endogenous nitrated fatty acids (NFAs), thought to be produced from NO, have recently been identified as important bioactive compounds present in human plasma. Although investigation of their biological activities is at an early stage, evidence is accumulating that they are potent anti-inflammatory molecules. Our preliminary data show that administration of exogenous NFAs can significantly attenuate pathophysiologic manifestations in a murine model of allergic airway disease, whereas inhibiting endogenous NFA synthesis exacerbates allergic responses. NFAs activate the nuclear transcription factor peroxisome proliferator-activated receptor-¿ (PPAR-¿) in some cell types, and we have found that allergic responses are exacerbated when PPAR-¿ is genetically eliminated but are attenuated by overexpression of PPAR-¿ in airway epithelial cells in vivo. Accordingly, we propose to test the hypothesis that activation of airway epithelial cell PPAR-¿ by nitrated fatty acids significantly suppresses the effects of allergic airway disease, including inflammation and mucus production. Our Specific Aims are: 1) to determine the extent to which NFAs modulate PPAR-¿ activity in the lung and the severity of murine allergic airway disease, for which we will use mice constitutively lacking all three isoforms of nitric oxide synthase (triple NOS knockout) and therefore expected to lack NFAs; 2) to determine whether PPAR-¿ activation in airway epithelial cells mediates NFAs' ability to inhibit effects of allergen challenge in murine allergic airway disease, for which we will utilize mice with PPAR-¿ either knocked out or overexpressed selectively in airway epithelial cells; and 3) to determine whether NFAs inhibit chemokine and mucus production in cultured human airway epithelial cells and the extent to which these effects are mediated through PPAR-¿-dependent and/or PPAR-¿-independent mechanisms, for which we will use gene silencing and chemical inhibition to suppress PPAR-¿ while testing for activation of other signaling pathways. For Aims 1 and 2 we will utilize an established murine model of allergic airway disease induced by cockroach allergen, while Aim 3 will be carried out in vitro using well differentiated primary human bronchial epithelial cells grown at an air-liquid interface. Validation of our hypothesis will identify and elucidate the mechanisms through which a novel endogenous substance modulates the severity of allergic airway disease and may lead to new therapeutic avenues and treatments for asthma.